Fuel-regulation system for steam-generators.



PATENTED MAY 21,1907.

- H. LEMP.

FUEL REGULATING SYSTEM FORSVTEAM GENERATORS.

Inventor, Hermannlvem 1c,

APPLIOATION'PILED NOV. 13. 1903.

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All I L i THE NORRI! Pan-Rs cm, WASHINGTON, u. c.

- UNITED STATES PATENT OFFICE.

I-IERMANN LEMP, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRICCOMPANY, A CORPORATION OF NEW YORK.

Specification of Letters Patent.

Patented May 21, 1907.

Application filed November 13, 1903. Serial No. 180,983.

To ctZZ whom if; TIMI/Z] concern:

Be it known that I, HERMANN LEMP, a citizen of the United States,residing at Lynn, county of Essex, State of Massachusetts, have inventedcertain new and useful Im' provements in Fuel-Regulation Systems forSteam-Generators, of which the following is a specification.

In automobile steam generating apparatus in which liquid fuel is used asthe heating agent it is the usual practice to provide means whereby thesteam generator and the fuel vaporizer of the burner may be maintainedat a suitable temperature at times when the vehicle is standing and thesystem is temporarily using no power, in order to have the apparatus inimmediate readiness for service. An auxiliary burner, commonly termed apilot, is generally employed for this purpose, and the heat of its flameserves to maintain steam in the generator, and also to keep the fuelvaporizer sufficiently hot to effectually vaporize the fuel when thesupply is opened, or in other words, the auxiliary burner is analogousin its function to the banking of the fire in ordinary boiler firingpractice.

My invention relates to a system of fuel regulation embodying thistwo-burner idea, and for which the supply of fuel is regulated by thethrottle that controls the delivery of steam to the engine. The throttleoperates to open or close the main supply of fuel to the burnersimultaneously as it opens or closes the supply of steam to the engine,and in direct continuity with the closing of the main supply theauxiliary supply of fuel is opened, or vice versa, so that the separatesupplies thus hold a reciprocal relation to each other.

In some systems there is aperceptible tendency for the vapor pressure ofthe burner to persist a certain period after the power is shut down, andthus furnish more vapor than is demanded. Obviously at this time whenthe power system is idle the forced draft flue is not operating and thevolume of air in the natural draft flue is not sufficient to support acomplete and clean combustion of the fuel, and consequently as soon asthe vehicle stops, the exhaust products of combustion emit obnoxiousodors. This same state of affairs exists while operating at light loadas when power, or in coasting down hill, where the quantity of steam islikewise practically negligible. With ordinary appliances however thepressure on the burner could not change rapidly enough to meet theseconditions so that the quantity of fuel supplied to the burner remainsfor a time largely in excess of the requirements and as a result theexhaust products become sooty and odorous. It is apparent therefore thatto provide a device for correcting these objections, which may beoperated by the throttle and act therewith with equal promptness, ishighly desirable and convenient. To provide such a device is the objectof the present invention and to carry it into practice a single burneris employed, but the fuel is supplied thereto in different quantities soas to produce the main working flame or the pilot or auxiliary flame,whichever may be desired. These two dif ferent supplies of fuel,,forconvenience, shall be distinguished hereinafter as the main fuel supplyand the auxiliary supply. The two supplies of fuel are so regulated asto hold a reciprocal relation to each other and one can be thrown intoservice simultaneously and in direct continuity with the cutting of the'other out of service, and the control of both is dependent upon theaction of the throttle.

The main supply operates in uniformity with the throttle so as to openand close when the throttle opens and closes, thereby regulating thefuel so as to prevent the quantity from exceeding what the conditions ofservice demand.

The flow of fuel from the auxiliary reservoir does not followimmediately upon closing the main fuel supply, because of the differencein pressures on the burner and auxiliary supply reservoir. The pressureon the burner at the time the apparatus is shut down is considerablyhigher than that of the reservoir, and as a consequence of opening theauxiliary supply at the time the apparatus is shut down a quick reliefis afforded for the pressure on the burner, and this sets up a momentaryflow to the reservoir from the burner and the connected pipes, until therelative pressures are equalized, after which the auxiliary supply takesplace under the initial pressure of the reservoir. This is an thevehicle is moving at low speed on a level important feature of thesystem as it permits road and demanding very little propelling l theburner pressure to be reduced simultaneously with the stopping ol. theforced draft, thereby preventing combustion. with a sooty flame everytime the apparatus is shut down.

The supplies of fuel are delivered from separate reservoirs, one ofwhich is at atmospheric and. the other under a higher air pressure. Aforce pump for the main supply of fuel is employed. and the auxiliarysupply is maintained. by the initial air-pressure on the fuel .in .itsreservoir.

In order to obtain the continuity with which the change is e'l'leotedfrom the main to the auxiliary supply of fuel, or vice versa,simultaneously with the elosing of the throttle, two methods may heemployed: First, the throttle may he n'ieehanieally oonneeted with. avalve which functions in sueh a manner as to out oil the main fuelsupply and at the same time open the auxiliary supply as the throttlecloses or vise versa, in one and the same operation; this obviates thenecessity of operating two sets of levers, namely the one controllingthe delivery of steam to the engine, and the other the supply or fuel tothe burner, thereby preventing contusion in manipulation as would likelyhe the with a multiplicity of operating lever; end, the live steam pipeon the engine side ol the throttle may he providr-id with a hraneh whichcommunicates with a pressure controlled needle valve that is adapted tocoin trol a bypass or connection from the pressure fuel reservoir. Thisneedle valve is automatieally operated by being suhiected to thepressure of the steam when the throttle valve is open, and is thereforeheld in closed position at such. times, whereas when the steam pressurelowers by closure of the throttle, the needle valve opens automatieallyto permit the auxiliary supply of heel from the pressure reservoir totake the place of the main supply for supporting the pilot .llame.

In the accompanying drawing, which illustrates one emhodinu-mt of myinvention, Figure 1 represents diagrammatic. lly a steam power systememploying a boiler with my improved fuel regulation; and Fig. 2 amodified term of regulator in which the auxiliary fuel supply is underhe control of the steam pressure on the engine side of thethrottle.

Referring to the drawing, 1. represents a steam generator of anysuitable type for producing superheate l. steam, which is inelosed in aeasing 2 and heated by a burner 3 heneath the generator in eo-operativerelation thereto. easing is provided with a nat- .r. 116 ural draft orup flue 4-. and a forced draft or down flue 5 by means of which thenecessary volume o'l air for supporting comlnistion, either while thevel'iiele is stationary or in op eration, is produced.

The supply of liquid to the steam or other vapor generator is taken froma reservoir 6 and is supplied through a supply pipe 7 to thege'i'ierator, a foot or hand pump 8 being stapes motors. One motorcomprises a::. (((fili lie 10 and a yielding (U1 "e tion. hetweoi. the

same and the pump piston. The (()1'.(( tion, iii the present case, is acrossliead a. d connecting rod co;.zstructioii i1 .1, a Frame formed ofside ror s 11 on. opposite sides ol' the pump and end pieces orhlllli'llltiits l i, and an. elastic memlier 12 between. the co.iieet'ig rod and the 'lrame. The connoclhg rod passes loosely throughthe adjacent (i'os:- piece and projects into the frame. The clasticmemlzer 12 is mounted or. the project i:.g 0;..d ol the coiniecti...grod, and co...sisis prol erahly oi annular I'Ulilitl' hull'ersussemlilod 01?. the rod and spaced apart l;y metal wasle ers. Thehull'ers arc (on'l'ined tetwce... :1 plate 12 on the 03 .d oil thecoi.:.1.-c "l'i rod and the cross-piece oi the frame, which i'oi'mai'iutineiits. The other cross-piece ii-1ri;. 'idl attached to the pumpplurger so that a: y movement of the Frame is imparled io the plunger.The motor just descriiled is ray anle o'l actuati g the plunger only ino..e lirccrior. and unalxle to return. it, i reason oi the loosecojnnectio. llOiVvtll the co. (w.- ing rod 11. and the adjace .tcross-piece,thus co..-.stituti g a lostemotion co....;e -L'io".. ll lsthe 'lu..'..ction ol the sccord motor to return the .)lu':;.ger afteriieiig actuated Ly the .llrs. motor. The second motor comprises a1,e:-;-- lQGQSlOj'. spr'" or springs 12-3, 'lixed at one o; d and securedto the Frame at the oiher, so that they are placed u. dcr tc1sio1: l2 lhe oporation oi the other motor.

The motors are so arranged that 'LlH discluirge stroke of the pump isperlormcd i the first motor aid the suction stroke l:y the second. Thetension. of the elastic memlrrr is adjusted so that the pump may deliverWater to the generator at a prcdol'ermi.ed pressure, and when or anyreason. the pressure on. the generator tcrds to i'icrwlsc, the elasticINQlHlIOI yields to a greater or less extent, thereby varying the strokeof l he pump to maintain the e lectivc supply ol" water ai constant orsulista tially constant pressure. By this arrangemegt the supply ofliquid io the generator may vary automatically accordance with thepressure oi the walor side of the geiicrator, and it iilMl'O l UX'Ovaries directly with the dcmaiid tor cam. The erator supplies steam to21 c gi e Lttluougli a live steam pipe 15 which is u. der co lrol ol' athrottle or regulator valve it The ex. haust side of the e?" tie iscoiiiii vied a pipe 17 to the rohea. chamber 151 locaied at the top ofthe lioiler using 2, and ilicrei the exhaust steam is supe'rlieatedlie'l'orc (lischarging into the down. l'lue 5 to (-rcaio a forceddra'lt.

iOO

llO

' burner.

In Fig. 1 two reservoirs for fuel are employed, one being the sourcefrom which the main supply to the burner is drawn and the other beingthe source from which the auxiliary supply is taken. The main supply offuel is delivered to the burner 3 by a fuel pump 19, from a source offuel under atmosphere pressure in a reservoir 20. Ihis pump is situatedin a supply pipe 21 between the reservoir and burner and is also of theva riable stroke type whereby its effective supply may be automaticallyvaried according to the pressure on the burner. The plunger of the pump19 is provided with a finger 22 which loosely engages with acorresponding finger 23 on the plate 12 of the connecting rod of themotor of the liquid pump, so that the fuel pump may be operated on itssuction stroke by the said rod, and a spring 24 connected to the pumpplunger at one end and fixed at the other to the pump cylinder, servesto perform the discharge stroke. With this arrangement the pump tends todeliver fuel to the burner at a certain pressure and if the pressure onthe burner tends to increase the fingers 22 and 23 will disconnect andthe spring 24 will yield and vary the stroke of the pump to such anextent that the quantity of fuel delivered thereby will be sufficient toenable the pressure to be maintained substantially constant on the Forthe purpose of supplying the burner while the steam generator is idle apressure reservoir or accumulator 25 is suitably provided and the fueltherein is placed under air pressure by means of a hand pump 26, shownin dotted lines, and the pressure most suitable for this purpose isabout ten pounds per square inch. This reservoir is preferably suppliedor filled from the reservoir 20 through a connecting pipe controlled bya stop cock 27. A drip or level pipe 28 is provided in the pressurereservoir and extends at its upper end adjacent to the top of thereservoir so as to determine the height of the fuel to afford space forthe desired head of air. This reservoir 25 is connected with the fuelsupply pipe 21 by means of a branch 29, and at the point of juncturethereof with the supply pipe a three-way valve 30, forming a fuelcontroller or regulator, is provided for controlling communicationbetween the burner and the separate reservoirs. This is preferablyarranged in close proximity to the throttle valve and they are bothmechanically connected by an arrangement of levers 31, so that byoperating the throttle the three-way valve 30 will be operated at thesame time. The valve 30 is operatively con nected with the throttle insuch a manner that by simultaneously closing the latter the main supplyof fuel from the pump will be cut off and communication be openedbetween the pressure reservoir 25 and the burner for establishing theauxiliary supply.

The pressure in the reservoir 25 is just sufficient to supply enough oilto the burner to support a pilot flame, without smoke or odor, foreffectually maintaining the steam in the generator in a state ofvaporization.

When the throttle is closed the exhaust from the engine is stopped andconsequently the forced draft ceases to operate. At this time thepressure on the burner is substantially at normal working pressure andthis should be immediately reduced so that the natural draft can supporta perfect combustion, otherwise the fuel would burn with considerablesmoke and odor. As the opening of-the auxiliary supply is simultaneouswith the cessation of the forced draft, the existing pressure on theburner may be relieved to the auxiliary reservoir, in accordance withthe relative difference of pressure. Then the pressures are equalizedthe fuel for the pilot flame will be received from the auxiliaryreservoir. This relief of pressure from the burner in case of repeatedstops at short intervals, as in city service, might tend to raise theinitial pressure in the reservoir above that desired. When thiscondition occurs a portion of the contents of the reservoir may be drawnoff, as by opening the valve in the gravity feed connection between themain and auxiliary reservoir thereby causing fuel to escape due to thepressure of the latter reservoir being higher than that in the former.

This arrangement of a single controller for the delivery of steam to theengine and the supply of fuel to the burner relieves care from the mindof the operator by not having to attend to these controlling devicesseparately, and it also provides a uniformity of regulation. It will beobserved, further, that by closing or opening the throttle the mainsupply of fuel is affected correspondingly, so that the fuel supplyvaries directly as the demand for the steam varies and thus affords moreeconomy in operation.

According to the modified form of regulator for the fuel, Fig. 2, thechanging from the main supply to the auxiliary supply, or vice versa,while not being mechanically controlled by the throttle, is,nevertheless, dependent upon the operation of the throttle. In otherwords, the pressure of the engine side of the throttle is utilized tocontrol the auxiliary feed from the pressure reservoir or accumulator25. In operation, as the main supply and the auxiliary supply hold areciprocal relation, and as the main supply is open while the throttleis open, it follows that when the throttle is closed the auxiliarysupply of fuel will be opened and the main supply will be closed. InFig. 2, as in Fig. 1, separate fuel reservoirs are employed, namely, areservoir 38 at atmospheric pressure for the main supply of fuel, and apressure reservoir 39 which is placed under any suitable initial surefuel to the burner and to admit fuel under low pressure to the burner asthe delivery of motive fluid to the engine is interrupted.

10. In combination, a burner, a main fuel supply pipe connected to theburner, an auxiliary supply pipe for supplying fuel to the burner at adefinite pressure, means for opening either supply pipe and closing theother, a pump in the main supply pipe for delivering fuel at arelatively higher pressure, and an automatic variable stroke mechanismfor the pump.

11. In combination, a burner, a main fuel supply pipe and an auxiliaryfuel supply pipe connected to the burner, a pump in the main supplypipe, actuating means for the pump provided with devices forautomatically maintaining the main supply of fuel at constant pressure,and means for closing the main fuel supply pipe and simultaneouslyopening the auxiliary fuel supply pipe or vice versa.

12. In combination, a burner, a main fuel supply tank, an auxiliary fuelsupply tank under air pressure, connections between the tanks andburner, a valved connection between the tanks, a pump for supplying fuelto the burner from the main tank, an automatic regulator for the pumpwhich tends to maintain the main fuel supply at constant pressure, andmeans for simultaneously interrupting the main fuel supply and openingthe auxiliary fuel supply to the burner or vice versa.

13. In combination, a steam generator and engine, a throttle forcontrolling the delivery of steam to the engine, a burner for thegenerator, means for delivering an auxiliary supply of fuel to theburner, means for delivering a main supply of fuel to the burner, aregulator for the latter means which tends to maintain the main supplyat a constant pressure, and means which simultaneously opens the mainfuel supply and closes the auxiliary fuel supply when the steam throttleopens or vice versa.

14. In a supply system, the combination of a burner, a main tank atatmospheric pressure, an auxiliary tank under air pressure, separatesupply connections between the tanks and burner, and a controlledconnection between the auxiliary tank and the main tank.

15. In a fuel supply system, the combination of a burner, a main tank atatmospheric pressure, an auxiliary tank arranged below the level of themain tank and adapted to be placed under air pressure, and a controlledconnection between the tanks which permits fuel to flow from the maintank to the auxiliary tank under gravity or to flow from the auxiliarytank to the main tank under air pressure in the former.

16. In a fuel supply system, the combination of a burner, a main tank atatmospheric pressure connected therewith, an auxiliary tank under airpressure also connected with the burner, means for placing the auxiliarytank under pressure, means for relieving the air pressure from theauxiliary tank, and a controlled connection between the tanks whichpermits fuel to flow from the main to the auxiliary tank when the latteris at atmospheric pressure or to flow from the auxiliary to the maintank when the former is under air pressure.

17. In a fuel supply system, the combination of a main supply tank atsubstantially atmospheric pressure, an auxiliary tank under a higherpressure, a burner connected with the tanks, a pump between the mainsupply tank and the burner, and a controlled connection for relievingthe pressure on the burner by discharging fuel into the auxiliary tank.

18. In a supply system, the combination of a burner, a main source ofliquid fuel at substantially atmospheric pressure, a second source offuel which is located below the level of the first, means for subjectingthe second source to an initial air pressure, a connection between thesources through which fuel feeds by gravity from the first to the secondsource, a valve normally closing the said connection, means forrelieving the pressure on the second source when it is desired to replenish it from the main source, a connection arranged to supply fuelfrom the main source to the burner, and a fuel pump in said connection.

In witness whereof, I have hereunto set my hand this tenth day ofNovember, 1903.

HERMANN LEMP.

Witnesses:

DUGALD MoK. MoKILLoP, JOHN A. MoMANUs.

